Sencha's Ext JS 6 Javascript framework is now generally available, and with it comes the ability to build Web apps for desktops, tablets and smartphones. But getting the user interface right isn't always easy.

There is pressure on IT departments to quickly build applications for different types of devices and OSes while keeping costs down, and that is helping Web apps gain ground, according to Art Landro, CEO at Sencha.

With this in mind, Sencha has combined its Touch framework with Ext JS to create a platform for building so-called universal apps for smartphones, tablets and desktops.

Ext JS 6 includes user interface widgets for HTML5 forms, menus and toolbars to speed up development time. There is a layout manager to help organize the display of data and content across multiple browsers, devices, and screen sizes.

But the availability of the tools doesn't guarantee success. The mistake companies make when developing apps for desktops with big screens, tablets and smartphones is to try to do too much on the latter.

"You can still do a lot, but you have to keep it simple," Landro said.

Ext JS 6 was first announced at SenchaCon in April. Nearly 2,000 existing customers registered for the beta and the feedback has mainly been positive, especially from large enterprise development teams that are developing complex business apps, according to Landro.

High on their wish list are more IDEs to choose from. Today, Ext JS is compatible with all commercial JetBrains IDEs, including IntelliJ. The company is planning to add Visual Studio before the end of the year, and Eclipse at some point.

Part of the Wednesday launch was an upgraded version of the company's management tool Space, which has been renamed Web Application Manager. Improvements include better reporting, analytics and debugging. It has been more tightly integrated with its other products, as well.

Sencha isn't the only company enamored with the potential for universal apps. It's the key building block of Microsoft's developer strategy for Windows 10. But the integration of mobile devices and desktops go beyond developer tools. For example, VMware-owned AirWatch is pitching its management tools for both worlds.

While Microsoft wants developers to create native applications, Landro is convinced Web apps will win in the enterprise. In part, this is because Android and iOS-based smartphones have become much better at running Web apps. He also believes Microsoft is on the right track with the new Edge browser.

Ext JS 6 is about 20 percent more expensive than the previous version of the framework. Sencha's decision to require a minimum of five licences has also angered some developers. But most users work in large organizations and the increased capabilities are worth the extra cost, according to Landro.

The Standard version costs from US$4,340. The Pro and Premium versions cost from $5,650 and $7,350 until Sept. 30. After that, they will be priced from $6,280 and $9,190.